A 15-year-old girl has been accused of spiking a family's drinking water with pesticide, resulting in the death of her four-year-old half-sister and illnesses among three other family members in Maha Sarakham province.
Borabue district deputy superintendent Pol Lt Colonel Mongkol Waidee said police had found that the slain toddler's 32-year-old mother had been arguing with her teenage daughter, who had a different father.
The mother, who lived with her new husband, the toddler's father, in Udon Thani and was visiting her parents' house in Tambon Nong Ko at the time, had reportedly turned down the teenager's request to have a boyfriend.
That disagreement reportedly stemmed from the teenager's inferiority complex as well as her assumption that the reason her mother hadn't invited her to live with her in Udon was that she didn't love her. It was then that the girl allegedly poisoned the drinking water when the others weren't at home.
Mongkol said that when police initially questioned the teenager, she broke down and admitted putting the pesticide into the water.
Officers will today interview the girl again in front of a multi-discipline committee - the extra interview is required in law when questioning a minor - before sending her for detention at a juvenile home, Mongkol added. The tragic incident took place at around 4pm on June 22 when the four family members drank water after eating a spicy meal.
The toddler drank the most, three cups, developed muscle weakness and had seizures as did two other children - her three-year-old sister and her seven-year-old cousin - while her mother suffered only muscle weakness.
The four were taken to hospital, where the toddler was pronounced dead.
The others are now said to be on the mend, although the cousin remained in hospital at press time last night.
The drinking water initially tested positive for pesticide of organophosphate compounds - which can cause muscle weakness, irregular heartbeats and even death when consumed in large quantities, according to provincial health office head Dr Phakhee Sappipat.
The National Institute of Health, Department of Medical Sciences, in Nonthaburi has retested the water to confirm the initial result and its findings should be out in a week, he said.
Meanwhile, the slain toddler's mother says will not take her for cremation tomorrow, as the mother had planned, because police have asked her to submit the body for post-mortem at Srinagarind Hospital in Khon Kaen to formally determine the cause of death.